I dislike the first one.
The second one would be nice without the ugly border.
The third one using a real life BG with a comic render was such a wise choice, effects are really nice.
I've noticed on the first 3 your blending is that great. I'd recommend working on your blending and lighting.
4th one is the best of all of them Lighting is great would look nice with a few more effects.
5th one is nice as well.
Sorry my CnC is so vague but I'm on my ipod at work.